1. Field of the Invention
The present invention relates to the field of computer systems and, in particular, to a method and apparatus for the automatic configuration of strapping options on a circuit board assembly.
2. Background Information
Recognizing that xe2x80x9cone size does not fit allxe2x80x9d in the computer industry, many computer system manufacturers offer a wide variety of computer systems to satisfy a variety of markets and budgets. While such variety makes personal computers available to a wider spectrum of consumers, the same product variety adds complexity to the manufacturing process which, when left unaddressed, may well result in quality and efficiency problems.
In an effort to improve efficiency and alleviate quality problems associated with the circuit board assembly process, many manufacturers have determined that it is more cost effective to settle on a few circuit board assembly xe2x80x9cplatformsxe2x80x9d. These platforms are essentially the same, or very similar, circuit board assemblies populated with similar components, wherein the operating characteristics of the circuit board assembly are determined by manually setting strapping devices to configure the configurable devices of the circuit board assembly. This manual setting of the strapping devices selectively configures a circuit board assembly xe2x80x9cplatformxe2x80x9d into a particular genre of circuit board assembly (i.e., a circuit board assembly suitable for a particular use/product). In other words, the selective configuration of strapping devices provide an otherwise generic circuit board assembly with the xe2x80x9cpersonalityxe2x80x9d characteristics (i.e., operating characteristics) commonly associated with a specific product. On, for example, computer system motherboards, strapping devices are often used to configure a clock source to supply a particular system bus clock frequency, or to indicate bus/core ratio (i.e., a the ratio of the bus clock frequency to the processor clock frequency) configuration information. Jumper blocks, dual-inline package (DIP) switches, double-pole single-throw (DPST) switches are but a few examples of strapping devices which are configured to select the operating configuration on a circuit board assembly.
Although the concept of the selective configuration of a generic circuit board assembly with strapping devices has indeed improved some of the efficiency problems, they have not eliminated the quality concerns and, in fact, have introduced new quality issues. For example, many of the prior art strapping devices are manually placed on the circuit board assembly in the manufacturing process, which is prone to human error. The misconfiguration of a circuit board assembly (i.e., the configuration of a strapping device which is inconsistent with the operating characteristics of a processor module) may well result in diminished performance or catastrophic failure for the consumer.
In addition to the quality and efficiency problems associated with prior art strapping devices, they do not lend themselves well to the upgrade of the circuit board assembly. For example, upgrading the central processing unit (CPU) to a higher performance processor may require that the strapping devices associated with the clock frequency and bus/core ratio be updated to take advantage of the performance characteristics of the higher performance processor. With many of the common prior art strapping devices, the reconfiguration of strapping options is performed by hand by a service technician. Just as in the manufacturing process, the manual reconfiguration of strapping devices in this manner is prone to human error and mechanical failure.
Thus a need exists for a method and apparatus for the automatic configuration of strapping options of a circuit board assembly, unencumbered by the deficiencies and limitations associated with the prior art.
In accordance with the teachings of the present invention, a method and apparatus for the automatic configuration of strapping options on a circuit board assembly is disclosed. In a first embodiment, a tenant processor module is shown comprising a processor core, a plurality of strapping devices, and an input bus. The plurality of strapping devices are configured to indicate configuration information to a receiving circuit board assembly coupled to the processor module. The input bus, coupled to the processor core, receives the configuration information back from the circuit board assembly and provides them to the processor core at a first time. At a second time, the input bus receives operational data from the circuit board assembly and provides them to the processor core.